I was recently chatting with an online buddy Cody and he asked how to achieve the reverse of the php function nl2br() so I showed him. At the same time I figured others could benefit from it so here is the function with an explanation.

Here is the function that uses preg_replace() to make the switch

function breakToNewLine($s, $useReturn=false) {
  return preg_replace('/(<br ?\/?>)/i', (($useReturn) ? '\r' : '\n'), $s);
}

The second parameter is used to determine whether or not a return should be used instead of a line feed.

The regular expression checks for the opening of a break tag "<", then the actual letters "br". At this point we might find a space, but we might not so we use a "?" which means it could match. Next we look for a possible / and escape this so the regex doesn't error out. Again we may or may not find a "/", so again we use the "?". We look for a closing to the break ">". The last thing to do is add an i modifier for a case insensitive search.

Nothing more to it really, a fairly simple function

Here is a sample

function breakToNewLine($s, $useReturn=false) {
  return preg_replace('/(<br ?\/?>)/i', (($useReturn) ? '\r' : '\n'), $s);
}

$string = "Hello, <br /> This is a test message.<br>With various 
versions of a break character.<BR>Here is some more random text.<Br /*gt; Finally one more.";
print breakToNewLine($string);